3D-printed drone offers hope to future missing aircraft

British researchers have 3D-printed a drone they say could be quickly deployed in emergencies such as the search for the missing Malaysian airliner.

The 1.5m-wide prototype unmanned aerial vehicle (UAV) was created for a research project that looked at 3D printing of complex designs without the need for removable support structures – something that could dramatically speed up the process.

But its designers at the Advanced Manufacturing Research Centre (AMRC) in Sheffield said the polymer craft could form the basis of cheap, disposable UAVs that could be built and deployed within as little as 24 hours.

‘I’d estimate that if someone had to build a UAV of this size from plans using traditional methods it would take them at least a working week,’ project lead Dr. Garth Nicholson told The Engineer.

Fellow researcher Mark Cocking added: ‘With the recent aircraft that’s been lost at sea, if you had a fleet of these you could send them out [to look for the aircraft] in 24 hours.’

3D printing techniques, such as the fused deposition modelling (FDM) used to make the drone, are now widely used to make rapid prototype versions of products without the need to first create expensive tools for traditional subtractive manufacturing.

But more complex structures that feature overhangs often require additional support structures to be built into the design (and then later removed), substantially adding to the design and build time.

‘The first time we…tried to do this it took over 120 hours to print,’ said Cocking. ‘If you have a bracket with a protrusion coming out more than 100mm, you’re going to have to build a support structure up to that to hold it in position. But every layer on this model is supported by the one below.’

Flight testing of an FDM-printed fixed wing UAV developed at the University of Sheffield AMRC

The UAV’s final geometry was designed specifically to be 3D printed although the overall shape is still similar to the original, he added: ‘We had to run multiple test pieces to see how we could push overhangs and feed that back into the CAD [computer-aided design] system to come up with the geometries that ultimately made this work.’

The craft comprises nine parts – two wings, two elevons, two spars, two wing end fences and a central spine – that can be easily snapped together and the largest of which is 750mm in diameter.

It weighs under 2kg and is made from ABS-M30, a thermoplastic designed to work with the Stratasys Fortus 900mc FDM machine, but the researchers believe using Nylon would make the drone 60 per cent stronger based on layer on layer adhesion for the same weight.

So far the drone has only been flown as a glider but the researchers said they plan to add an electric fan propulsion system by replacing the central spine and eventually develop the craft for guidance by GPS or cameras, controlled by an operator wearing first person-view goggles.

‘The endgame for us is to build a 3m version,’ said Nicholson. ‘At the moment the plan is to use as much rapid prototyping technology as possible. None of the UAVs of a similar size and capability out there, as far as we know, use unsupported FDM.’